v
ABSTRAK
Eva Kholisoh, I0312028. PENGEMBANGAN MODEL PERSEDIAAN CLOSED LOOP SUPPLY CHAIN DENGAN MEMPERTIMBANGKAN INSPEKSI, SORTING, WASTE DISPOSAL, DAN REWORK. Skripsi. Surakarta: Program Studi Teknik Industri Fakultas Teknik, Universitas Sebelas Maret, September 2016.
Dalam penelitian ini dikembangkan suatu model persediaan closed-loop supply chain dengan mempertimbangkan inspeksi, sorting, waste disposal, dan
rework. Terdapat tiga pihak yang terlibat dalam model yakni pengecer, pemanufaktur, dan pemasok. Permintaan pengecer dipenuhi dari produk hasil produksi reguler dan remanufaktur. Dalam model persediaan ini telah mengakomodir dua proses pemulihan terhadap barang bekas pakai yakni
remanufacturing dan refurbishing. Barang bekas pakai yang tidak dapat dipulihkan sampai pada kualitas yang sama seperti sedia kala akan dikategorikan ke dalam
refurbishable item yang nantinya dijual ke pasar sekunder. Produk cacat yang dihasilkan dari produksi reguler akan dilakukan proses rework. Dalam penelitian ini menerapkan single production cycle – multiple remanufacturing cycle atau kebijakan (1, R) dan multiple production cycle – single remanufacturing cycle atau kebijakan (P, 1). Fungsi tujuan dari model persediaan ini adalah maksimasi total profit gabungan dari pihak pengecer-pemanufaktur-pemasok, dengan enam variabel keputusan yaitu waktu siklus pengecer, jumlah siklus remanufacturing
untuk kebijakan (1, R), jumlah siklus produksi reguler untuk kebijakan (P, 1), frekuensi pengiriman produk jadi dari pemanufaktur ke pengecer pada fase remanufaktur, frekuensi pengiriman produk jadi dari pemanufaktur ke pengecer pada fase produksi reguler, dan frekuensi pengiriman bahan baku dari pemasok ke pemanufaktur. Prosedur iterative diberikan untuk mendapatkan variabel keputusan yang optimal. Numerical example diberikan untuk menggambarkan situasi yang sesuai dengan model yang dikembangkan. Hasil analisis sensitivitas menunjukkan bahwa parameter yang paling berpengaruh terhadap fungsi tujuan profit gabungan dan nilai optimal variabel keputusan adalah parameter permintaan, proporsi
recoverable item, dan biaya simpan serviceable item.
Kata Kunci: closed-loop supply chain, inspeksi, sorting, waste disposal, rework
produksi, remanufaktur, refurbish
xvii + 162 halaman; 58 gambar; 21 tabel
vi
ABSTRACT
Eva Kholisoh, I0312028. INVENTORY DECISION IN A CLOSED LOOP SUPPLY CHAIN WITH INSPECTION, SORTING, WASTE DISPOSAL, AND REWORK. Thesis. Surakarta: Undergraduate Program of Industrial Engineering Department, F aculty of Engineering, Sebelas Maret University, September 2016.
In this research, we develop a closed-loop supply chain by considering inspection, sorting, waste disposal, and rework. There are three parties involved in the model, namely retailer, manufacturer, and supplier. The retailer’s demand is satisfied by newly manufactured items or remanufactured items. The model uses two recovery processes toward used items, namely remanufacturing and refurbishing. The recoverable items which cannot be r ecovered to as good as new item, will be categorized as refurbishable items and will be sold to the secondary market. The defective items produced from manufacturing system will be reworked. This research applies single production cycle – multiple remanufacturing cycle or (1,R) policy and multiple production cycle – single remanufacturing cycle or (P,1) policy. The objective function of the model is to maximize the total joint profit from retailer-manufacturer-supplier, with six decision variables, namely retailer’s time cycle, frequency of remanufacturing cycle for (1,R) policy, frequency of production cycle for (P,1) policy, delivery frequency of finished items from manufacturer to retailer in the remanufacturing phase, delivery frequency of finished items from manufacturer to retailer in the regular production phase, and delivery frequency of raw material from supplier to manufacturer. An iterative procedure is suggested to obtain the optimal decision variables. A numerical example is presented to illustrate the application of the model. Senstivity test results show that objective function (joint profit) and optimal value of each decision variables are most influenced by demand, proportion of recoverable item of the whole return item, and manufacturer’s holding cost fraction for the serviceable inventory.
Keywords: closed-loop supply chain, inspection, waste disposal, rework manufacturing, remanufacturing, refurbishing
